Vehicle

This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2022-007793 filed on Jan. 21, 2022.

The present disclosure relates to a vehicle equipped with a battery.

In recent years, as a specific measure against climate variation of the earth, efforts to realize a low-carbon society or a decarbonized society have been actively made. In vehicles, a reduction in CO2 emission amount is strongly required, and a driving source is rapidly electrified. Specifically, a vehicle such as an electrical vehicle or a hybrid electrical vehicle has been developed which includes an electric motor as a driving source of the vehicle, and a battery as a secondary battery which can supply electric power to the electric motor.

In such a vehicle, normal charging in which a battery is charged by being connected to an external power supply or rapid charging in which a current larger than that in the normal charging flows through the battery to charge the battery can be performed (for example, JP-A-1107-046701 and JP-A-2006-112932). Since the battery generates heat at the time of charging and discharging, it is necessary to appropriately cool the battery. In particular, the battery is likely to generate heat during rapid charging. When the battery generates heat at a temperature equal to or higher than a predetermined temperature, an output of the battery is restricted from the viewpoint of safety.

On the other hand, an air conditioning device (so-called air conditioner) is mounted in a vehicle in order to make an occupant comfortable in the vehicle. Since the air conditioning device requires a relatively large amount of electric power, when the air conditioning device is operating during charging, the battery may not be appropriately cooled and it may take extra time to charge the battery. In particular, in a vehicle including a cooling device in which a refrigerant in a cooling circuit (refrigeration cycle) for an air conditioning device and a refrigerant in a cooling circuit for cooling a battery can exchange heat in a heat exchanger, the cooling performance is restricted, so that there is room for consideration as to how to balance the time required to charge the battery and the use of the air conditioning device.

Further, the time required to charge the battery and the use of the air conditioning device are preferably determined based on an intention of an occupant, and uniform determination made by a vehicle side may impair convenience of the vehicle.

The present disclosure is to provide a vehicle capable of balancing a time required to charge a battery and use of an air conditioning device without impairing the convenience.

According to an aspect of present disclosure, there is provided a vehicle including: a battery configured to store electric power from an external power supply; a cooling device including a battery cooling device configured to cool the battery, an air conditioning device configured to adjust a temperature inside a vehicle cabin, and a heat exchange unit configured to exchange heat between a refrigerant of the battery cooling device and a refrigerant of the air conditioning device; and a control device configured to control the cooling device, charging of the battery, and a battery temperature, in which: the control device notifies a destination arrival time based on a required charging time in a state where the air conditioning device is operated when charging is included in a scheduled travel plan; before the charging is executed, the control device makes a proposal for permission to restrict use of the air conditioning device during the charging; and when the proposal is approved, the control device changes the destination arrival time based on a required charging time in a state where the use of the air conditioning device is restricted, and notifies the destination arrival time.

According to the present disclosure, the time required to charge the battery and the use of the air conditioning device can be balanced without impairing the convenience of the vehicle.

Hereinafter, an embodiment of a vehicle of the present disclosure will be described with reference to the accompanying drawings.

[Vehicle]

is a diagram illustrating a configuration of a vehicle. As illustrated in, the vehicleincludes, for example, a motor MOT, driving wheels DW, a power control unit, a battery BAT, a battery sensor, a charging port, a charger, a communication device, a cooling device, a navigation device, and a control device. In, a thick solid line indicates mechanical connection, a double dotted line indicates electric wiring, and a thin solid line arrow indicates a control signal or a detection signal. The control signal or the detection signal is transmitted through such as a serial communication line, a wireless communication network, or a multiplex communication line such as a controller area network (CAN) communication line. The configuration illustrated inis an example, and a part of the configuration may be omitted or another configuration may be added.

The motor MOT is, for example, a three-phase alternating current motor. An output of the motor MOT is transmitted to the driving wheels DW, and power is generated using kinetic energy of the vehicle during deceleration of the vehicle.

The power control unitincludes, for example, an inverterand a DC-DC converter. The DC-DC convertersteps up the electric power supplied from the battery BAT and outputs the stepped-up electric power to the inverter, and steps down the electric power supplied from the inverterand outputs the stepped-down electric power to the battery BAT. The inverterconverts a direct current supplied from the DC-DC converterinto an alternating current and outputs the alternating current to the motor MOT, and converts an alternating current generated by the motor MOT into a direct current and outputs the direct current to the DC-DC converter.

The battery BAT is, for example, a secondary battery such as a lithium ion battery. The battery BAT is charged with electric power introduced from an external power supplyoutside the vehicle, for example, a quick charger. The battery BAT mainly supplies electric power to the motor MOT. Examples of the battery sensorinclude a voltage sensor, a current sensor, or a temperature sensor. The voltage sensor, the current sensor, and the temperature sensor detect a current value, a voltage value, and a temperature of the battery BAT, respectively. The battery sensoroutputs the detected current value, voltage value, temperature, or the like to the control device.

The charging portis connected (plugged) to the external power supplyvia a charging cable. The connection between the vehicleand the external power supplyis not limited thereto. For example, the vehiclemay be provided with a power receiving coil or the like which can contactlessly receive electric power transmitted from the external power supply.

The chargeris provided between the battery BAT and the charging port. The chargerconverts a current introduced from the external power supplyvia the charging port, for example, an alternating current at the time of normal charging, into a direct current. The chargeroutputs the converted direct current to the battery BAT.

The communication deviceincludes a wireless module for connecting a cellular network or a Wi-Fi network. The communication devicecommunicates with a weather information serveror the like via a network NW, for example, the Internet or the Ethernet.

[Cooling Device]

As illustrated in, the cooling deviceincludes an air conditioning device (air conditioner)and a battery cooling circuit. Hereinafter, the air conditioning deviceis referred to as the air conditioner. A refrigeration cycleis formed in the air conditioner, and the air conditioneradjusts environment in a vehicle cabin by adjusting a state of air in the vehicle cabin. An operation of the air conditioneris controlled by a cooling control unit, which will be described later, which receives an operation of an occupant (hereinafter, also referred to as a user). The battery cooling circuitcools the battery BAT, the charger, and the power control unitby causing a refrigerant to flow through a refrigerant flow path. A heater may be provided in the battery cooling circuitto heat the battery BAT. An operation of the battery cooling circuitis controlled by the cooling control unitto be described later such that a temperature of the battery BAT is maintained within a predetermined range. In the cooling device, the refrigeration cycleof the air conditionerand the battery cooling circuitare configured such that the refrigerants can exchange heat with each other via a chiller.

More specifically, with reference to, a compressor, a condenser, an expansion valve, and an evaporatorare disposed in series in the refrigeration cycleof the air conditioner, and a second flow pathin which another expansion valveand the chillerare disposed is provided in parallel with a first flow pathin which the expansion valveand the evaporatorare disposed. Further, a shutoff valveis provided between the expansion valveand a branch portionof the first flow pathand the second flow path, and the refrigerant flows to both the first flow pathand the second flow pathby setting the shutoff valveto an ON state, and the refrigerant flows only to the second flow pathby setting the shutoff valveto an OFF state.

In the battery cooling circuit, a pump EVP for supplying the refrigerant, the chiller, the battery BAT, the charger, the power control unit, and a radiatorare connected in series.

In the chiller, heat exchange is performed between the refrigerant in the refrigeration cycleand the refrigerant in the battery cooling circuit. Therefore, in the cooling device, a cooling capacity of the refrigeration cycleof the air conditioneris distributed for the air conditioner and for battery cooling. That is, when the air conditioneris not used (air conditioner OFF), the shutoff valveis in the OFF state, and all the cooling capacity of the refrigeration cyclecan be used for the battery cooling. On the other hand, when the air conditioneris used (air conditioner ON), the shutoff valveis in the ON state, and the cooling capacity which can be used for the battery cooling among the cooling capacity of the refrigeration cycleis reduced by an amount distributed for the air conditioner. Therefore, among the cooling capacity of the refrigeration cycle, the cooling capacity which can be used for the battery cooling depends on ON/OFF of the air conditioner.

[Navigation Device]

Next, an example of a configuration of the navigation devicewill be described with reference to. As illustrated in, the navigation deviceincludes a processor, a memory, a GPS unit, a display unit, an operation unit, and an interface. The componentstoare connected to each other via a bus.

The processoris, for example, a CPU which controls the entire navigation device. The memoryincludes, for example, a main memory such as a RAM and an auxiliary memory which is a nonvolatile memory such as a flash memory. The main memory is used as a work area of the processor. The auxiliary memory stores various programs for operating the navigation device. The programs stored in the auxiliary memory is loaded into the main memory and executed by the processor.

The auxiliary memory of the navigation devicealso stores map data used for specifying a current position of the vehicle, route guidance to a destination, and the like. Although detailed description is omitted, the map data includes road data representing roads on which the vehiclecan move, facility data representing information on each facility, and the like.

The GPS unitreceives GPS signals (radio waves) from GPS satellites and measures the current position of the vehicle. The current position measured by the GPS unitis used to specify the current position of the vehicle.

The display unitincludes a display which displays characters and images, a graphic controller which controls the entire display, and a buffer memory such as a video RAM (VRAM) which temporarily records image data of an image to be displayed on the display. The display is, for example, a liquid crystal display or an organic EL display.

The operation unitinputs an operation signal corresponding to an operation received from the user to the inside of the navigation device(for example, the processor). The operation unitis, for example, a touch panel. In addition, the operation unitmay be a remote controller, a keyboard, a mouse, or the like including a plurality of keys.

The interfacecontrols input and output of data between the navigation deviceand the outside (for example, a charging control unit). The interfaceis controlled by the processor. A part or all of the functions of the navigation devicemay be implemented by, for example, functions of a terminal device such as a smartphone or a tablet terminal owned by the user of the vehicle.

[Control Device]

As illustrated in, the control deviceincludes a motor control unit, a battery control unit, the cooling control unit, and the charging control unit. The control deviceis implemented by an electronic control unit (ECU) including a processor, a memory, an interface, and the like. The motor control unit, the battery control unit, the cooling control unit, and the charging control unitmay be configured as separate control devices.

The motor control unitcontrols the motor MOT based on an operation amount on an accelerator pedal. The battery control unitcalculates a state of charge (SOC) of the battery BAT based on an output of the battery sensorattached to the battery BAT. The cooling control unitcontrols the cooling devicebased on the output of the battery sensorin order to cool the battery BAT, and controls the air conditioning deviceaccording to a user operation. The charging control unitcontrols the chargerduring normal charging, and controls charging of the battery BAT by communicating with the external power supplyduring rapid charging. The charging control unitis configured to communicate with the navigation device.

[Air Conditioner Use Restriction Proposal Control]

In the vehicleconfigured as described above, when the user registers a destination with the navigation device, a scheduled travel plan from the current position of the vehicleto the destination is displayed on the display unit. The scheduled travel plan includes charging at a charging station CS located on a travel route or near the travel route in consideration of the SOC of the battery BAT. In addition, the required time is displayed on the display unittogether with the travel route. The scheduled travel plan may be a plan in which one travel route is displayed, or may be a plan in which one travel route is selected from a plurality of travel routes by the user.

is a diagram illustrating an example of the display uniton which the scheduled travel plan and a graph including a required time for each scheduled travel section are displayed.

For example, assuming that the current position of the vehicleis a point A and the destination is a point D, the scheduled travel plan includes charging at the charging station CS at a point C between the point A and the point D. Accordingly, the user can drive the vehicletoward the destination (point D) without worrying about the vehiclebecoming unable to travel due to low power so-called power shortage). In a case where charging is not necessary before the vehicletravels to the destination, it is needless to say that charging may not be included in the scheduled travel plan.

As illustrated in, a required travel time (75 minutes) from a current location (point A) to the point C where the charging station is located, a required charging time (25 minutes) at the charging station CS, a required travel time (60 minutes) from the point C to the point D which is the destination, a total travel distance (250 km), and a total required time (150 minutes) are displayed on the display unit. Therefore, the user can accurately know a destination arrival time including the required charging time. It is sufficient that the contents displayed on the display unitinclude the travel route to the destination and the required time to arrive the destination, and additional information, layout, and the like may be appropriately changed. The travel route and the required time do not have to be displayed on the same screen, and may be separately displayed by switching the screen.

As the required charging time, a required charging time at the charging station CS on the assumption that the air conditioneris used is displayed. As described above, in the cooling device, the cooling capacity of the refrigeration cycleof the air conditioneris distributed for the air conditioner and for the battery cooling, so that the required charging time may vary depending on a use state of the air conditioner.

More specifically, as described above, when the battery BAT is charged, the battery BM generates heat. When the battery temperature of the battery BAT becomes equal to or higher than a predetermined temperature (hereinafter, also referred to as an output restriction temperature) due to the heat generation, the output of the battery BAT is restricted from the viewpoint of safety. When the output of the battery BAT is restricted, a current supplied from the external power supplyto the battery BAT decreases during charging of the battery BAT. In particular, at the time of rapid charging, since a large current is supplied, the temperature of the battery BAT is likely to rise.

Therefore, in a situation where the cooling performance for cooling the battery is not sufficient due to the use of the air conditioner, the battery temperature becomes equal to or higher than the output restriction temperature, the current supplied to the battery BAT is restricted, and accordingly, the required charging time becomes longer. On the other hand, if the battery BAT can be sufficiently cooled by the battery cooling circuitby stopping the air conditioner, the output of the battery BAT is not restricted and the required charging time is shortened.

Therefore, when the cooling performance for cooling the battery is equal to or lower than the cooling capacity at which the battery temperature can be maintained at a temperature lower than the output restriction temperature before the charging is executed, the charging control unittransmits, to the navigation device, a display instruction for displaying that the required charging time is shortened by restricting the use of the air conditioner. Further, the charging control unittransmits, to the navigation device, a display instruction for displaying a proposal for permission to stop the air conditioner. Therefore, for example, at a point B (not illustrated) located between the point A and the point C, as illustrated in, the display unitdisplays a proposal that “Are you in a hurry? The required time for rapid charging will be shortened by restricting the use of the air conditioner during charging.”. Further, icons of “permit” and “not permit” are displayed on the display unit. That is, the charging control unitproposes the user to permit restriction on the use of the air conditionerduring charging.

When the user wants to shorten the required charging time, the user can select “permit” to shorten the required time to arrive the destination. In this case, the charging control unitchanges the destination arrival time based on the required charging time in a state where the use of the air conditioneris restricted, and displays the destination arrival time on the display unit.

is a diagram illustrating a graph including the required times changed due to the air conditioner use restriction. As illustrated in, the required charging time at the charging station CS is changed and displayed on the display unit(25 minute->15 minutes).

On the other hand, when the user wants to stay in the vehicle and use the air conditionereven during charging, by selecting “not permit”, the user can also continue to use the air conditionerin the vehicle during charging although the required charging time cannot be shortened. In this way, the user can shorten the required charging time and the destination arrival time with his/her intention. Since the air conditionercan be continuously used when the user has sufficient time and wants to use the air conditioner, the convenience of the vehicleis not reduced.

As described above, the charging control unitdetermines the necessity of proposal based on the cooling capacity of the air conditionerin the cooling deviceand the cooling capacity of the battery cooling circuitin the cooling device. When the battery BAT can be sufficiently cooled by the battery cooling circuiteven if the air conditioneris used, that is, when the battery BAT can be maintained at a temperature lower than the output restriction temperature, it is not necessary to make the above-described proposal.

For example, when a temperature of a region where the charging station is located is low, it may not be necessary to make the above-described proposal. Therefore, it is preferable that the charging control unitacquires weather information from the weather information servervia the communication deviceas illustrated inand determines the necessity of the proposal based on the weather information. In this manner, when a situation in which the battery temperature is likely to become high is grasped in advance based on the weather information and it is not necessary to restrict the use of the air conditioner, the above-described proposal is not made, and thus it is possible to avoid making unnecessary proposals to the user.

Further, when the user selects “permit” in response to the proposal, the charging control unitpreferably displays, on the display unit, sightseeing guidance such as sightseeing information, restaurant information, and shopping information in the vicinity of the charging station CS. As a result, the user can be guided from the inside of the vehicle where the use of the air conditioneris restricted to the outside of the vehicle, and chances of the user using the air conditionerduring charging, which will be described later, can be reduced.

The proposal may be made at the point A, between the point A and the point B, immediately before arrival at the point C, or at the time of arrival at the point C.